A Non-interventional Study to Identify Children and Adolescents With ADHD and With or Without mGLuR Mutations

Inclusion Criteria: 1. Parent/legally authorized representative (LAR) can speak and read English fluently, have provided informed consent and agree to be contacted for an interventional study prior to being genotyped. 2. Subject is 6 to 17 years of age (inclusive) at the time of informed consent. 3. Parent/LAR confirms that the subject has been diagnosed with or been told by a doctor that their child has ADHD. 4. Parent/LAR confirms that the subject is not pregnant and/or breastfeeding. Exclusion Criteria: 1. Parent/LAR confirms that the subject has been diagnosed with any of the following conditions (aside from ADHD): conduct disorder, anxiety disorder, major depression, autism spectrum disorder (ASD), bipolar disease, psychosis, hypertension, seizure disorder, syncope, or other serious cardiac problems. 2. Aside from your child's current ADHD medication (if applicable), parent/LAR confirms that the subject is currently taking any of the following medications: antidepressants, anti-anxiety medications, anti-psychotics, and/or mood stabilizers. 3. Parent/LAR confirms that the subject has been genotyped previously in the MDGN-NFC1-ADHD-001, MDGN-NFC1-ADHD-101 clinical study.